Stimulated emission

The transcript explains how photons interact with atoms or molecules when struck by another photon of the right energy. This interaction is crucial in lasers, where it generates a beam of photons that share the same frequency and direction.

What happens when an atom or molecule is hit by a photon with the right energy?

• It changes its frequency.

• It splits into smaller atoms.

• It emits a photon.

• It absorbs the photon and remains unchanged.

What is the primary function of a laser in terms of photon production?

• To absorb photons of different frequencies.

• To create a beam of photons with varying energies.

• To generate a beam of photons with the same frequency.

• To scatter photons in multiple directions.

Which of the following best describes the direction of photons in a laser beam?

• They travel in circular paths.

• They travel in random directions.

• They travel in the same direction.

• They travel in opposite directions.

What characteristic do the photons in a laser beam share?

• They have different frequencies.

• They have different wavelengths.

• They have the same frequency.

• They have varying speeds.

How does a laser ensure that photons travel in the same direction?

• By using a vacuum to guide photons.

• By using a magnetic field to align photons.

• By using mirrors to reflect photons.

• By using a lens to focus photons.